Frequency dependent power ¯uctuations: a feature of the ESR system or physical?
Abstract. The k-dependence of the received power in high signal-to-noise ratio �SNR) conditions, occurring for naturally enhanced ion-acoustic lines �NEIALs) and for real satellites, is investigated by using the EISCAT Svalbard Radar �ESR), where the data are recorded in eight separate channels usin...
| Main Authors: | , , |
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| Format: | Text |
| Language: | English |
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| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.210.1493 http://www.ann-geophys.net/18/1224/2000/angeo-18-1224-2000.pdf |
| Summary: | Abstract. The k-dependence of the received power in high signal-to-noise ratio �SNR) conditions, occurring for naturally enhanced ion-acoustic lines �NEIALs) and for real satellites, is investigated by using the EISCAT Svalbard Radar �ESR), where the data are recorded in eight separate channels using di€erent frequencies. For the real satellites we ®nd large variations of the relative powers from event to event, which is probably due to a di€erent number of pulses catching the satellite over the integration period. However, the large power di€erence remains unexpected in one case. Over short time scale � 10 s) the relative power di€erence seems to be highly stable. For most NEIAL events the di€erences between channels are within noise level. In a few cases variations of the relative power well above both the estimated and expected 1-sigma level occur over a signal preintegrated pro®le. We thus suggest that the frequency dependence of the power in NEIAL events has its origin in the scattering medium itself as the most plausible explanation. Key words: Ionosphere �auroral ionosphere; plasma waves and instabilities; instruments and techniques) 1 |
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